The present invention is generally related to traffic signal lights including those incorporating solid state light sources, and more particularly to pedestrian signals known as PED heads.
Traffic signal lights have been around for years and are used to efficiently control traffic through intersections. While traffic signals have been around for years, improvements continue to be made in the areas of traffic signal light control algorithms, traffic volume detection, and emergency vehicle detection.
Pedestrian head signals have also been around for years and help inform pedestrians whether it is safe to cross a street, and also if it is safe to continue crossing a street. Unfortunately, this signalling to a pedestrian can be confusing since it is often unknown how much time remains before an associated traffic light changes states. A blinking xe2x80x9cdon""t walkxe2x80x9d or xe2x80x9cstop handxe2x80x9d signal confuses a pedestrian since it may be unknown the time to cycle change. A pedestrian halfway across a street may not know if there is still time to continue crossing.
There is desired an improved pedestrian head signal capable of discretely signaling pedestrian at a far side, and half-way across a street whether it is safe to cross or continue crossing, respectively.
The present invention achieves technical advantages as split phase pedestrian head signal adapted to inform a pedestrian at a far side of a street and at the middle of a street whether it is safe, from the respective position, to cross or continue crossing the associated street.
The solid state light apparatus has a first array of LEDs having an upper portion and a lower portion, and a first lens disposed over the first LED array. A control circuit selectively controls each of the first LED array portions, whereby the upper portion in combination with the lens generates a first light beam in a first direction, and the LED array lower portion in combination with the lens generates a second light beam in a second direction being different than the first direction. Each of the light beams has a beamwidth of about 10xc2x0, with the first light beam being directed toward and viewable by the pedestrian at the far side of the associated street, and the second light beam being directed to and viewable by a pedestrian at the middle of the street. A second similar solid state light apparatus is provided having a similar array of LEDs having an upper portion and a lower portion, and a second lens disposed over the second LED array. The control circuit selectively controls the upper and lower LED array portions to generate a third and fourth light beam in a third and fourth direction, respectively. The third light beam is directed toward the pedestrian at the far side of the street, and the fourth light beam is directed at a pedestrian half-way across the street. The first light apparatus first and second light beams illuminate a xe2x80x9cwalkxe2x80x9d symbol, and the second solid state light apparatus third and fourth light beams illuminate a xe2x80x9cdon""t walkxe2x80x9d symbol.
According to the method of the present invention, in a first state of operation, the xe2x80x9cwalkxe2x80x9d symbol is illuminated by both the first and second light beam and is ascertainable by a pedestrian both across the street and half-way across the street. In a second state of operation, the second light beam is generated such that a walk symbol is viewable by a pedestrian half-way across the street, but wherein the third light beam is generated to illuminate the xe2x80x9cdon""t walkxe2x80x9d symbol which is viewable by a pedestrian across the street. In the third state of operation, only the third and fourth light beams are generated such that the xe2x80x9cdon""t walkxe2x80x9d symbol is ascertainable by a pedestrian both across the street and half-way across the street.
The split-phase pedestrian head is advantageous in that it provides a better indication to a pedestrian whether or not it is safe to start walking across the street, and whether or not a pedestrian half-way across the street should continue to cross the street or remain at the center of the street until the next light cycle.